Respiratory effects of CO2 pneumoperitoneum during transperitoneal laparoscopic urological surgery

To evaluate the effects of CO2 pneumoperitoneum on respiratory function during urological laparoscopic surgery with exposure of the retroperitoneal space in the lateral decubitus position.

Arterial blood gas analysis and measurements of the partial pressure of CO2 in exhaled gas (PetCO2) were performed during CO2 pneumoperitoneum in 12 patients who underwent transperitoneal laparoscopic surgery for the retroperitoneal organs (the retroperitoneal group): the results were compared to those of 11 patients who underwent laparoscopic varicocelectomy (the varicocele group) with the same anesthesia and intra-abdominal pressure.

The increase in PaCO2 and PetCO2 and the decrease in arterial pH during CO2 insufflation were significantly greater in the retroperitoneal group than in the varicocele group. PaCO2, PetCO2 and arterial pH continued to change in the retroperitoneal group, whereas these values reached a plateau at 30 min after the beginning of CO2 insufflation in the varicocele group.

The respiratory effects of CO2 pneumoperitoneum are more pronounced during laparoscopic urological surgery with opening of the retroperitoneum. It is possible that exposure of the retroperitoneal space increased CO2 absorption during insufflation.